Key milling machine



Jan. 30, 1934. E. E. KAHL 1,945,276

KEY MILLING MACHINE Filed Nov. 6, 1930 4 Sheets-Sheet 1 INVENTOR ErnesfE. K ahl BY Filed Nov. 6, 1930 4 heets-Sheet 2 INVENTOR grn 251 E. Kahl.#6.

ATTORNEY Jan. 30, 1934. KAHL 1,945,276

KEY MILLING MACHINE 4 Sheets-Sheet 3 Filed Nov. 6, 1930 INVENTOR ErnestE.Kahl.

ATTORNEY Jan. 30, 1934.

E. E. KAHL 1,945,276

I KEY MILLING MACHINE Filed Nov. 6, 1930 4 Sheets-Sheet 4 Patented Jan.30, 1934 UNITED STATES KEY MILLING MACHINE Ernest E. Kahl, Ncm Britain,Conn, assignor to The B. Jahn Manufacturing Company, New Britain, Conn,a corporation of Gonnecticut Application November 6, 1930. Serial No.493,803

14 Claims.

This invention relates to automatic milling machines, and moreparticularly to a key-milling machine employing a rotary cutter forforming longitudinal slots in the face of the key.

One object of this invention is to provide a milling machine of theabove nature in which the rotary cutter is mounted upon a shaftjournaled in the end of a cam-actuated lever whereby the height of saidcutter may be controlled at all points of the cutting stroke.

A further object is to provide a milling machine of the above nature inwhich the cutter shaft is connected by a flexible coupling with astationary motor-driven shaft.

A further object is to provide a key-milling or key-warding machine ofthe above nature in which the keys are carried in a recess of aninclined plate slidable in the bed of the machine.

A further object is to provide a machine of the above nature in whichthe key-holding nest plate has a depending stop member adapted to engagethe machine body to limit the length of the stroke thereof andaccurately aline the key recess with the key magazine.

A further object is to provide an improved form of camand-lever operatedkey ejecting mechanism.

Afurther object is to provide an improved form of bell-crank levermechanism for reciprocating the nest plate under the rotary cutter.

A further object is to provide a machine of the above nature which willbe relatively simple in construction. inexpensive to manufacture, easyto install and adjust, compact, and very eificient and durable in use. I

With these and other objects in view there has been illustrated on theaccompanying drawings one form in which the invention may beconveniently embodied in practice.

In the drawings:

Fig. 1 represents a rear view of the key-milling machine, showing theinterior operating mechanism.

Fig. 2 is a side sectional view of the machine taken along the line 22of Fig. 3.

Fig. 3 is a top View of the same.

Figs. 4 and 5 are fragmentary sectional views of a portion of themechanism showing the inclined nest plate in its extreme upperkey-receiving and lower key-ejecting positions respectively.

Fig. 6 is a fragmentary sectional View of the milling cutter, nestplate, and ejecting mechanism, the section being taken along the line6-6 of Fig. 3, looking in the direction of the arrows. 1 Fig. '7 is asectional view taken along the lin '7---'? of Fig. 3. Referring now tothe drawings in which like reference numerals denote corresponding partsthroughout the several views, the numeral 10 indicates the main frame ofthe machine and the numeral 11 the base upon which the frame is mounted.The frame 10, which is open at the rear, consists of a front wall 12,side walls 13 and l 14, and an inclined top wall 15. The top wall 15 isadapted to support a key-holding nest plate' 16 mounted to slide in apair of opposed guiding jaws 17 and 18 formed in said top wall 15.

Key reciprocating nest plate The nest plate 16 is provided at its lowerforing an adjusting screw 20, the point of which is adapted to engagethe lower front end of; the top wall 15. In order to support akey 21ward end with a depending stop flange 19 carryduring the millingoperation, the nest plate 16 is provided with a key-shaped recess. ornest 22 in the top face thereof. The keys 21 are adapted to be fed downinto said nest 22 successively from an upwardly-extending magazine 23.

Ey'ecting mechanism In order to eject the key 21 from the nest or 3recess 22 in the plate 16 at the conclusion of the cutting stroke afterthe key 21 has been I moved downwardly past a rotary milling cutter 24,provision is made of an ejecting mechanism comprising a pair of headedrods 25 and 26 having their lower ends screwed into a movable bottomplate 27 which is slidably housed within a rectangular socket 28 formedin said nest plate 16 underneath the nest 22 thereof. I 25 and 26 aresurrounded by coiled springs 29 and 30, whereby when the nest plate16,.is in its The rods lower position, as shown in Fig. 5, the bottomplate 27 will lie in alinement with the upper end of a downwardlyextending ejector rod 31 mounted to reciprocate in a sleeve 32 dependingenlarged adjustable yoke 33.

The yoke 33 is provided with a laterally ex- 7' downwardly by a spring34. The lower end of said rod 35 has a roller 37 mounted thereon 3 forengaging the upper surface of a lever 38 pivoted upon a tie bolt 39adjacent the front wall from said p Wall 15, said rod 31 carrying an 12of the machine (see Fig. 2). The upper end of the lever 38 has a roller40 journaled thereon which is adapted to engage a cam 41 keyed orotherwise secured in non-rotative relation upon a cam shaft 42.

The cam shaft 42 is adapted to receive continuous. rotary motion bymeans of a worm gear 43 rigidly mounted on said shaft and which mesheswith a worm 44 on a main shaft 45 carrying a pulley 46 adapted to bedriven by a belt, not shown. The opposite end of the shaft 45 isprovided with a hand wheel 46 for convenience in adjusting the machinebefore the power is turned on.

Nest plate reciprocating-mechanism In order to cause the nest plate 16to slide up and down in its inclined passage in the top wall 15 of theframe 10, said nest plate is provided with a depending yoke 47 carryinga horizontal pin 48 which is adapted to be embraced by a U-shaped uppersection 49 of a T-shaped bell-crank lever 50 pivoted to a tie-bolt 51extending; between the side walls 13 and 14; The

lever 50is'provided adjacent its midsection witha.rearwardly andupwardlyinclined arm 52 having an eye 53for receiving a vertical elongatedcoiled spring 54. the bottom end of said spring being fastened to ahorizontal tie bolt 55 extending between said side frames 14 and 15 andlocated just above the base 11 ofthe machine (see Figs. 1 and2).

The, lever 50 is provided with a lower arm 56 carrying a roller 57 inalinement with an ovalshaped cam 58 mounted on the cam shaft 42,

whereby the desiredreciprocating motion is imparted to the nest plate16. The cam 58 is so shaped that the nest plate will be movedsuccessively-to bring the key recess or nest 22*underheath the stack ofkeys 21 in the magazine 23, the depth of said recess, being such. thatonly one key will be-withdrawn from underneath said stack; The nestplate 16 will then slide down in the guideways 17 and 18 until the uppersurface of said key has been milled as shown in Fig. 2; and bringingthe'plate. 16 from the position shown in Fig. 4 to the position shown inFig. 5. At this time a lug 59'on-the cam 41 will come into actionraising the ejecting rod. 31 and forcing the bottom plate 27 upwardlyagainst.

the springs 29 and; 30. The rods 25 and 26 will thus be caused to ejectthe milled key 21' from the nest 22'per1m'tting it to slide by gravityforwardly down the inclined nest plate 16 and to be caught in a suitablereceptacle, not shown.

Cutting mechanism The rotary milling cutter 24. is adaptedto be securedon a cutter shaft. 60. journaled in a pair of bearingsv 61 and, 62carried by a bifurcated adjustably held bya gib 64d, 2. pair of setscrews- 64'e, and a pair of lock; nuts 64 The bearings 61 are adapted.to be pressed upwardly at all times-bye pair of cup-shaped plungers 61alocated in a circular hole'6'1c in the plate 649 below the shaft andhaving coiled springs 6417.

By means of this construction the cutter height will: be maintainedaccurately as determined by the. micrometer adjustment on the front ofthe rocker lever 63.

The lateral guideways 64b and 64c form part of a plate 64g slidable indovetailed longitudinal guideways 64h and 647' integral with the topwall 16. The forward portion of the lever 63 is provided with a slot 65for receiving a knurled micrometer nut 66 having a graduatedcircumference 66a surrounding an adjusting screw 67, the lower end 68 ofwhich is adapted to engage the upper end 69 of a cutter-operating rod70, permitting the depth of the milled slot to be readily adjusted.

In order to adjust the plate 64g in a longitudinal direction, provisionis made of a knurled micrometer adjusting screw 70a mounted in anupstanding ear 70b of a horizontal strip 700 at the front of the topwall 15 and a knurled screw 70d carried in a boss 70c on the rear partof said top plate 15.

Small set screws 71 and 711 are also provided on the front end of thelever 63 immediately behind and in front of the screw 67 for locking theknurled nut 66 and screw 67 in adjusted position. The rod 70 extendsdownwardly through the top wall 15 and is provided intermediate its endswith a collar 72 having a set screw 73 passing therethrough foradjusting the tension in a coiled spring 74 located above said collar.The lower end of the rod 70 is provided with a roller 75: adapted toliein contact with the lever 76 pivoted on the tie bolt 39 and having aroller 77 on its upper edge. The roller 77 is adapted to engage at alltimes with a cam 78 carried by the cam shaft 42.

The shape of the cams58 and 78 are so arranged that the cam 78 willcause the front end of the lever 63- to beraised for depressing theshaft 60. to lower the cutter 24 after thekey has first been broughtbeneath it, the key remaining stationary during the downward motion ofthe cutter. The nest plate will then move slowly past therevolvingcutter causing parallel slots to be milled in the key whichwill be then moved beyond the cutter into ejecting position.

In order to permit the cutter lever 63 to be laterally adjusted withrespect to the plate 64g, provision is made of a pair of knurledmicrometer screws 79 and 80 carried by said lugs 81 and 82. The threadedends of the screws 79 and 80 are adapted to. extend inwardly intoengagement with a pair of plugs 83 and 84 upstanding from said andhaving a shaft 87 mounted to rotate on 2.

fixed axis. In order to permit the cutter shaft 60 to rise and fall.under the action of the cutter operating cam 78, provision is made of aflexible coupling comprising a spool-shaped central member 83 and a pairof side collar members 89-and 135.

90 rigidly mounted on the shafts 87 and 60 respectively. Each of theflanges of the spoolshaped member 88 is provided with a pair of opposededge recesses 91, said recesses-being adapted to be located 90 degreesaway from a pair of similar recesses 91a in the flanges of the collarmembers 89 and 90.

A pair of flexible circular discs 92, such as leather, rubber, etc., arelocated between the ends of the spool member 88 and the flanges on the45 collars 89 and 90, said flexible discs 92 being secured in positionas by bolts 93 and nuts 94 ex tending in alternate directions, the headsof said bolts being located outside of the flanges andthe nuts locatedin the recesses 91.

In order to prevent the keys 21 from chattering during the millingprocess, provision is made of a downwardly convex curved spring finger95 having a T-shaped base 96 yieldably carried by a laterally projectingplate 97 secured to the end of the top wall 15. The base 96 of thespring finger 95 is loosely mounted on a pair of pins 98 and 99 and ascrew 100, the central screw 100 having a head 101 on its upper end andbeing surrounded by a coiled spring 102, whereby the spring finger95'will be pressed downwardly at all times.

Operation In operation, assuming the plates 64a and 64g to have beenpreviously adjusted as desired, the keys or other articles 21 will befed downwardly by gravity from the magazine 23 and successively receivedin the nest recess 22 of the nest plate 16. The nest plate 16 will thenbe caused to slide downwardly by the cam 58 and bell-crank lever 50 intomilling position, the rotary cutter 24 being until then held in itsuppermost position as shown in Fig. 4. The nest plate will then remainstationary for a short period and the cutter will then be lowered by theaction of the cam '78 until it has reached the full depth of the slot tobe milled continued rotation of the cam 58 will cause the key-holdingnest plate to slide downwardly past the cutter, producing a straightslot in the key extending from a point within the key bow to theextremity of the bit.

When the nest plate 16 reaches the ejecting position shown in Fig. 5,the lug 59 on the cam 41 will come into action causing the lever 38 toraise the rod 35 and eject the key from the nest recess 22, whereuponthe key will slide by gravity down the nest plate 16 and drop into thereceptacle, not shown.

While there has been disclosed in this specification one form in whichthe invention may be embodied, it is to be understood that this form isshown for the purpose of illustration only, and that the invention isnot to be limited to the specific disclosure but may be modified andembodied in various other forms without departing from its spirit. Inshort, the invention includes all the modifications and embodimentscoming within the scope of the following claims.

Having thus fully described the invention what is claimed as new and forwhich it is desired to secure Letters Patent is:

1. In a milling machine, a frame having a top wall, a pair oflongitudinal parallel guideways in said top wall, an article-holdingplate slidable in one of said guideways, a second plate adjustable inthe other guideway, a transverse guideway in said second plate, a rotarycutter shaft-supporting plate in said transverse guideway, and means toadjust said second plate with respect to said article-holding plate.

2. In a milling machine, a frame having a top wall, a pair oflongitudinal parallel guideways in said top wall, an article-holdingplate slidable in one of said guideways, a second plate adjustable inthe other guideway and having a transverse guideway, a rotary cuttershaft-supporting plate adjustable in said transverse guideway, means forreciprocating said article-holding plate, and means for automaticallyraising and lowering said cutter for milling said article.

3. In a milling machine, a frame having a top wall, a pair oflongitudinal parallel guideways in said top wall, an article-holdingplate slidable in one of said guideways, a second plate adjustable inthe other guideway and having a slidable in one of said guideways, asecond plate adjustable in the other guideway and having a transverseguideway, a third plate adjustable in said transverse guideway, a leverpivoted on said third plate, a rotary cutter 'journaled in the rearofsaid lever, and cam-and-lever operated means for alternately raising andlowering the front of said lever to bring said cutter into and out ofmilling position.

5. In a milling machine, a frame having a top wall, a pair oflongitudinal parallel guideways in said top wall, an article-holdingplate slidable in one of said guideways, a second plate.

adjustable in the other guideway and having a transverse guideway, athird plate adjustable in said transverse guideway, a lever pivoted onsaid third plate, a rotarycutter journaled in the rear of said lever,means for alternately raising and lowering the front of said lever tobring said cutter into and out of milling position, and means on saidlever for varying the depth of cut of said cutter.

6. In a milling machine, a frame, an articleholding plate slidablelongitudinally on said frame, a spring-pressed bell-crank lever in saidframe for reciprocating said plate, means for ejecting said articleafter the milling operation, a cutter-holding shaft mounted on an axisparallel to said frame, means for rocking said shaft about its axis tobring the cutter into and out of milling position and vary the depth ofcut, and cam-and-lever operated means to actuate said lever, saidejecting means, and said rocking means.

7. In a milling machine, a frame, a rotary cutter mounted on said frame,an article holding plate slidable on said frame, means for moving saidplate to bring said cutter in alinement with said article at a pointintermediate the ends thereof, means for holding said articlestationary, means for lowering said cutter to the full depth of the slotto be milled, and means for thereafter moving said plate to cause saidcutter to produce a slot extending from said intermediate point to oneend of said article.

8. In a key-warding machine, a frame, a rotary cutter mounted on saidframe, a key-holding plate slidable on said frame, means for slidingsaid plate in said frame to bring a point in the key bow under saidcutter, means for automatically lowering said cutter to the full depthof cut while said key is held stationary, and means for thereaftersliding said plate to mill a slot extending from the starting positionto the end of the key bit.

9. In a key-warding machine, a frame, a rotary cutter mounted on saidframe, a key-holding plate slidable on said frame, means for slidingsaid plate in said frame to bring a point in the key bow under saidcutter, means for automatically lowering said cutter to the full depthof out while said key is held stationary, means for thereafter slidingsaid plate to mill a slot extending from the starting position to theend of the key bit, and. means for ejecting saidkey; after themillingoperation.

1,0. In a key-warding machine, a frame, arotarycuttermounted on saidframe, a key-holdingplate slidable on said frame, means for sliding saidplate, insaid frame to, bring, a point in the, key bow under saidcutter, means for automati-v cally lowering said cutter to the fulldepth of out while said key is held stationary, meansf or thereaftersliding said plate to mill a slot extending from the starting positionto the end of the key bit, andcam-and-lever-operated means for ejectingsaid key after the milling operation.

11. In a milling machine, a frame, a rotary a cutter mounted on ahorizontal axis, an article holding plate slidable under said cutter,means for moving said plate to bring said article into milling position,means for automatically lowering said cutter to start the cut at a pointintermediate the ends of said article, means forholding said articlestationary while saidcutter is being lowered, and means to thereafterslide said plate along said frame tomill a slot tothe end ofv saidarticle.

12,. In a milling machine, a frame, an article holding plate slidablelongitudinally in said frame, a second plate slidable transversely onsaid frame, a lever adjustably mounted on said: second plate on an axisparallel to said frame, a rotary cutter journaled in said lever,cam-operated means for rocking said lever to raise and" lower saidcutterto vary the: depth of" cut during thecutting operation as the articlepasses under saidcutter, and manually operated means for en-..gagingsaid lever for adjusting said cutter.

13'. In a milling machine, a frame, an article holding plate slidablelongitudinally in saidplate, means for sliding said key-holding plate tobring the bow of said key under'said cutter,

means for lowering said cutter to the full depth of out while holdingsaid key stationary, means for thereafter cutting a slot to the end ofthe key bit, means on said plate for ejecting the key' after the millingoperation, and a resilient plate carried by said frame and overlyingthe-path of said plate for pressing upon said key during the millingoperation to prevent chattering.

ERNEST E.

